This 288-Million-Year-Old Fossilized Scrap of Skin Is the World’s Oldest #fossils #paleontology #oklahoma #skin #reptile

The earliest known fossil of epidermis was preserved due to unique circumstances. Current Biology Mooney et al.

Smithsonian Magazine has an article about the discovery of the old fossilized skin.  The specimen belonged to a lizard-like reptile that lived about 288 million years ago during the Permian Period.  It was found in a cave near Richards Spur, Oklahoma.  This specimen represents the oldest known preserved skin.  The previous record was about 130 million years younger.  More detail can be found in the paper published in the journal Current Biology.

Paleontologists have been going back to Richards Spur for years. “It’s an exceptional locality,” says study author and University of Toronto paleontologist Ethan Mooney. Hundreds of millions of years ago, fine-grained sediment filled in fissures of an ancient cave system—burying the remains of early amniotes and other animals within. What makes Richards Spur special, however, is a unique interaction between the clay-rich cave sediment, a lack of oxygen, and oil that seeped from the cave rocks.

Most living things decay and completely break down after death, leaving no trace in the fossil record. Preservation is rare to begin with, and to find skin is even more unusual. In this case, the ancient animal remains buried within the cave were likely left in a relatively dry area with low oxygen. The tough skin, with scales made out of the same material as your fingernails, was able to desiccate and stand a better chance of being buried with the animal’s bones.

When the remains of prehistoric animals became buried in the Richards Spur cave, hydrocarbons seeped out of the cave’s stone to combine with sediment to create what Mooney calls “exquisite fossils.” That oil came from the transformed remains of even older fossil organisms that lived in the seas about 330 million years ago. The organic remains essentially turned into petroleum, which then interacted with the skin and bones of the animals buried in the cave and preserved the skin in three-dimensional detail. Those fossils helped to create new fossils that have survived for hundreds of millions of years.